The invention relates to an automated multi-step process for the production of glazings.
Multi-step production lines have previously been used in the manufacture of automobile glazings. German Patent Publication No. 29 45 682 C2 describes a series of workstations including a cutting station where a linear score is made on a rectangular blank, and a break-off station where the blank is broken at the score. Prior art production lines also typically comprise stations for grinding the edges of a glass sheet, measuring the contour of the glass sheet, making holes, and inscribing indicia on the glass sheet. Production lines for laminated glazings can also include stations which assemble glazings and glazing components, or equip already assembled glazings with accessories such as frames, mirror bases, attachment clamps or other parts.
Conveyance of glass sheets in the prior art is performed on horizontal conveyors where the sheets rest on belts, conveyor rollers or other similar devices. In these conveyor systems, the sheets must be positioned at every work station in a specific orientation to insure proper completion of the task. To do this, stops are provided which act on the edges of the glazing to force the glazing into the desired position. Unfortunately, such use of stops causes the sheets to slide somewhat on its bottom side, which can lead to surface flaws (i.e. scratches, abrasions, etc.) and even to broken sheets.
Automated positioning of workpieces at the various workstations is known in other arts. For example, German Patent Publication No. 27 41 647 A1 describes a production line comprising multiple workstations, and hence, multiple work tools. Here, workpieces are attached to pallets which are routed to the workstations on vehicles. More specifically, the vehicles comprise a rotating platform utilized to drop off pallets having completed workpieces and to pick up pallets having workpieces which require work. Additionally, some production lines include handling units used to automatically position workpieces at the workstations, which allows for good precision during positioning. This technology is described in greater detail in a prospectus DE of the BOSCH company entitled Bosch Flexible Automation, 11/83.
In a prospectus of the Siemens Company entitled "A System For Storage of Parts and Pallets," 1984, an automated production line is described in which workpieces are conveyed to separate workstations via magazines from which they are removed and positioned on the production machines. Finally, assembly automatons are known wherein a collection of parts pass through various workstations which perform the required assembly tasks. This procedure is described in detail in a prospectus DE of the OKV company, 1989.
Thus, the prior art includes several techniques for the economic and efficient assembly of various parts. However, no such system exists for glazings.